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Another method for suppressing voltage spikes is the transient voltage suppression diode (TVS). Although diodes do not have as much capacity to conduct large surges as Metal Oxide Varistor, diodes are not degraded by smaller surges and can be implemented with a lower "clamping voltage". Metal Oxide Varistor degrade from repeated exposure to surges and generally have a higher "clamping voltage" so that leakage does not degrade the Metal Oxide Varistor. Both types are available over a wide range of voltages. Metal Oxide Varistor tend to be more suitable for higher voltages, because they can conduct the higher associated energies at less cost.

Another type of transient suppressor is the gas tube suppressor. This is a type of spark gap that may use air or an inert gas mixture and often, a small amount of radioactive material such as Ni-63, to provide a more consistent breakdown voltage and reduce response time. Unfortunately, these devices may have higher breakdown voltages and longer response times than varistors. However, they can handle significantly higher fault currents and withstand multiple high-voltage hits (for example, from lightning) without significant degradation.